1. Field of the Invention
This invention relates to a method and an apparatus for analyzing the composition of gasoline-range petroleum products using a new copper on silica gel adsorption composition. More particularly, this invention relates to a copper on silica gel adsorption composition which can separate olefins in a composition comprised of olefins and saturates.
2. Description of the Prior Art
The present standard procedure for analyzing gasoline-range petroleum products is the fluorescent indicator adsorption (FIA) technique described in American Standard Test Measurement (ASTM) D-1319. This ASTM test covers the determination of saturates, olefins, and aromatics in petroleum fractions that distill below 600.degree. F. (315.degree. C.). The test involves a lengthy analysis requiring continuous operator attention and is subject to human variability and several interferences, such as aromatic olefins, some diolefins, and compounds containing sulfur, nitrogen, or oxygen being determined as aromatics. These limitations have inspired the development of numerous alternatives which have met with varying degrees of success. Of the various alternatives, most are gas chromatographic methods, all of which share a common weakness. This weakness is that the olefins, instead of being separated from the saturates and aromatics and measured directly, are permanently trapped. This means that the amount of olefins present in the sample cannot be measured directly and must be calculated by difference. Using such a system, false measurements are obtained, especially in samples containing only small amounts of olefins because one would be comparing a small difference between two relatively large values.
The present invention satisfactorily solves this separation and measurement problem by providing an apparatus and a method for directly measuring the hydrocarbon composition of a sample.
The general object of this invention is to provide a method and an apparatus for directly analyzing the composition of gasoline-range petroleum products. More specifically, the object of this invention is to use a copper on silica gel adsorption composition to separate olefins from a composition comprised of olefins and saturates.
A further object of this invention is to provide an improved method for analyzing gasoline compositions quickly and reliably.
Still further, an object of this invention is to provide a direct volume percent measurement and digital readout of the saturates, olefins, and aromatics in a gasoline sample.
Other objects of this invention will become apparent to one skilled in the art based upon the ensuing description.